Re: [PATCH v3] docs: allow long unbroken headings to wrap and prevent overflow

[Rito Rhymes]

I tested the issues in the following environments:

Windows 10 desktop:
- Chrome
- Firefox
- Edge

Kali Linux under WSL2:
- Chromium
- Firefox

Android 16 mobile:
- Chrome
- Firefox
- Edge

I put together a screenshot catalog of my test results in each
environment, the images are hosted in a GitHub issue and referenced
here. Note that on mobile, when horizontal scroll overflow occurred,
I zoomed out to show the full page width exceeding the header width
to demonstrate the broken layout it caused.

The two cases I used were:

Long slash-delimited string:
https://docs.kernel.org/6.15/userspace-api/sysfs-platform_profile.html

Long underscore-delimited string:
https://docs.kernel.org/6.15/userspace-api/gpio/gpio-v2-line-get-values-ioctl.html

Results by environment:

Windows 10

Chrome:
- slashes: horizontal overflow
  https://github.com/user-attachments/assets/2189783c-0328-4079-a1f0-8aead03e4041
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/d351eb45-44bb-4ae3-8e2c-055a929c776b

Firefox:
- slashes: wraps normally
  https://github.com/user-attachments/assets/fe6667d2-1559-4a50-a1e8-feada0dadd3b
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/b7ee8a66-0c41-457d-b699-9b825fb8b5a1

Edge:
- slashes: horizontal overflow
  https://github.com/user-attachments/assets/703c4e0a-ad0c-42a1-bda6-356a2bc9c609
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/08fa2762-22c4-48b7-aaa4-d418bcc83b62

Kali Linux under WSL2

Chromium:
- slashes: horizontal overflow
  https://github.com/user-attachments/assets/5a25a590-fb84-4445-9bb0-baf069498e41
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/dfa38ba2-2c2b-49af-bd39-31852157e82f

Firefox:
- slashes: wraps normally
  https://github.com/user-attachments/assets/cd736918-4f48-48fe-b18d-822dd2e6727b
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/6ff9e12f-f0b6-445b-a372-aebc93e4a951

Android 16 mobile

Chrome:
- slashes: horizontal overflow
  https://github.com/user-attachments/assets/ea05ef9f-b7ba-4d18-8828-fd3ec7a3db49
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/a4d088ee-d385-499d-bc05-03b8e19870ef

Firefox:
- slashes: wraps normally
  https://github.com/user-attachments/assets/84018ee9-8c87-4d00-99dc-c4569bd16e2c
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/c694acae-18d7-48a1-abcd-a2ae208cfa73

Edge:
- slashes: horizontal overflow
  https://github.com/user-attachments/assets/c5f110f8-3ee8-4490-89f4-d8da33e4f37d
- underscores: horizontal overflow
  https://github.com/user-attachments/assets/4486cb0a-53c1-4d5f-bcc6-d61680133a2c

So the pattern I saw was:

- Long slash-delimited strings wrapped normally only in Firefox, on
  all three environments I tested. In every other browser/environment,
  they caused page-wide horizontal scroll overflow.
- Long underscore-delimited strings caused page-wide horizontal
  scroll overflow in every browser/environment I tested.

If it is easier to review the screenshots in one place,
I collected them in this GitHub issue with environment
headings:

https://github.com/ritovision/linux-kernel-docs/issues/2

That issue may also be a convenient place to add your own
screenshots to host and reference here for comparison.

Rito